Gasoline gauge



u 11, 1929- H. B. MARSHALL 7 1,717,051

GASOLINE GAUGE Filed May 18, 1925 2 Sheets-Sheet 1 June 11, 1929.

H. B MARSHALL GASOLINE GAUGE 2 Sheets-Sheet 2 Filed May 18, 1925 /(//v/7/0/v GZQc'u/r five/750m 5W; 2. M w

Patented June 11, 1929.

UNITED STATES 1,717,051 PATENT OFFICE.

HARRY B. MARSHALL, 01 ST. LOUIS, MISSOURI; EDWARD W. TERRY, ADMINISTRATOR OF SAID MARSHALL, DECEASED, ASSIGNOR, BY MESN E ASSIGNMENTS, TO PHOEEBE B. MARSHALL, OF CHICAGO, ILLINOIS.

GASOLINE GAUGE.

Application filed May 18, 1925. Serial No. 30,991.

My invention relates to means for indicating the level ofa liquid and for permitting the indication to be displayed either v intermittently or continuously at a point 6 located at any desired distance from the liquid. More particularly, my invention relates to an electrically operated liquid level indicator, one of its general purposes being that of providing a compressible resistance in circuit with a source of current and an ammetcr, and of subjecting this resistance to pressure responsive to the buoying effect of the liquid. Furthermore, in invention aims to provide an appliance or this purfl pose which can readily be attached to any 1i uid container, which will not be seriously atlected by vibrations of the liquid, whic will not permit oscillations of the liquid or the container to open the circuit, which caneasily be adjuste( and which can readily be constructed so as to afford readings accurately proportioned to the depth of the liquidm a container of-any given shape.

My invention also provides a device of this kind particularly suitable for use in the gasoline tanks of automobiles and easily attachable to such tanks, and one which will not include gearing,'rotatable shaft or. other friction producing mechanism in the constructionof the current controllin device.

It likewise provides a device wl iich can readily be employed with low voltage battery currents, either in connection with a se arate battery or with the i ition circuit of the automobile, and whic can be em:

ployed with equal facility for indicating the amount of lubricating oil in the corresponding oil chamber of the automobile. Furthermore, my invention provides a device of this kind which can readilyqbe constructed in varying lengths for the same. height of a liquid container, so as to have the zero'reading of the indicator correspond either to a substantially complete emptying of the container, or to a consumption of the liquid down to a point merely leaving a reserve supply. i

Still further and also more detailed objects will appear from the following specifications and from the accompanying drawings, in which Fig. 1 is a diagrammatic view showing an embodiment of my invention as employed in connection with a separate battery circuit and with a liquid tank having the general shape of a cylinder which has its axis horizontal.

Fig. 2 is an enlarged central and vertical section through the current-controlling device and the liquid container of Fig. 1.

Fig. 3 is a horizontal section taken of Fig. 2 along the line 33.

Fig. 4 is a erspective view of the inner clamping mem er used in fastening the current controlling device of Fig. 2 to the top of a tank.

Fig. 5 is a diagram showing desirable circuit connections for the same device when the controlling current is supplied through entirely insulatedvv conductors by the battery of an lgnition circuit.

Fig. 6 is a similar diagram showing correspon ing connections en a ground return is employed.

Fig. 7 is a central and vertical section through the upper portion of a current controlling device showing another embodiment of my invention.

Fig. 8 is a horizontal section taken through Fig. 7 alon the line 77.

Fig; 9 is a somewliat diagrammatic view showing a simplified embodiment of my invention as employed in a separate receptacle attached to a liquid container.

In one of its immediate commercial applications, my invention is particularly adapted for use upon automobiles in giving the driver a continuously visible indication of the amount of gasoline in the gasoline tank of his car, or of the amount of lubricating oil which his ear is carrying. I-

am therefore illustrating my invention in connection with such embodiments, although I do'not wish to be limited as to the uses of the same.

Fig. 1 shows a tank 1 containing a liquid the current flowing through a circuit connected to the two ends of the carbon pile. This circuit is here shown as including a battery 5, a fixed resistance 6 and an ammeter 7, it being obvious that the ammeter can be mounted at any distance from the by suitably lengthening the conducting portions 8 of the circuit,

.and also that the circuit as a whole can be controlled by any suitable switch 9. By suitably calibrating the ammeter, I can make I its indications correspond to varying levels of the liquid, such as the full, half and empty level markings of Fig. l. I

To make the current controlling device readily attachable to an ordinary liquid container, I desirably construct it so that the entire device, including the circuit connections, can all be carried by a stem which is clamped'to the top of the container, such as the metal stem 10 of Fig. 2. This metal stem has a longitudinal bore, the lower portion of which houses. a

' member 3 is desirably 7 it houses both the portion of the stem 10in head 18 ofthe 'lowerpresser member soas V 23 extending through the-washer 19 and carbon pile 4 and also a portion of the lower presser member 12 which directly supports the carbon pile 4:. The said bore likew1se houses an upper presser head --13 bearing against the top of a carbon pile and carry-- which the carbon pile is mounted and the lower presser member, which presser member 12may' have its bottom directly engaging the bottom 16 of the said bore in the buoyed member as shown in Fig. 2. Then I interpose a flexible member, such as a quite light spring 17, between the lower end of the stem 10 and the enlarged lower to maintain a continuous electricalconnectionbetweenthe lower presser member and the stem 10.

v To guide the buoyed member for .-vert ical movement with respect to the stem 10, I provide a disk 19 which slidably fits the upper portion 20 of the bore in-the buoyed member. I also interpose a. compression spring 21 between this disk 19 and a: later-.

ally projecting flange 22 on the stem 10,

so that the spring continuously tend to.

lift the washer 19. This washer is conneeted to the buoyed member by a pair of screws threaded into the buoyed member, so that an adjusting of these screws will compress the spring 21, thereby causing the thrust of this spring to raise the buoyed member with respect to the stem 10. Thus arranged,

the spring 21 can counteract the efiect of gravity on the buoyed member to any desired extent, thereby permitting the device to be adjusted to a high degree of the sensitiveness and also 'permitting an adjustment of a minimum compression to which the carbon pile is subjected when in use. After the screws 23 have been adjusted for this purpose, the upper part of the bore 20 can be filled with wax' (as shown at 39) so as to seal this bore.

For the circuit connections, I am here showing a wire 24 clamped between a pair of nuts 25 and 26 which are threaded on the stem 10, and a companion wire 27 resting upon a washer 28 which is insulated from the top of the stem 10 and clamped against this washer by a nut 29 threaded on the shank 11 of the upper prcsser me1n her. The nut 26 also serves as a support for the main portion of the device, being disposed immediately above a rubber washer 30 which rests on a perforated plate 31, which plate bears against the top of the tank 1 and extends across an opening in the latter. Opposed to this perforated plate 31 is a companion plate 32 which is clamped against the top 1 of the tank by the tightening of the nut 26. To effect this clamping I provide the stem 10 with a shoulder supporting awasher 42 which in turn supports the top of a surge-preventing casing 33 and another washer 34 above the latter, there desirably being a rubber washer 35 interposed between the washer 3l and'the clamping plate 32. V

The casing or shield 33 is here shown as a cylinder closed at both ends except for a relatively small air vent 35 close to its upper end and a pair of ports 36 in the bottom 37 of the hollow cylinder. This bottom 37 is also shown as slidably guiding a guide stem'38 which is fastened to the lower end of the buoyed member 3 in axial alinement with the stem 10 and the carbon pile and which 'de' stem terminates at some distance a ove the bottom 40 of the tank.

With the parts thus arranged, liquid poured into the tank will enter the interior of-the casing 33 through the inlets 36 and hence will assume a level corresponding to the general level of the liquid in the tank, so that the buoyed member will be subjected to a corresponding lifting efi'ect and hence will exert a proportionate upward pressure on the carbon pile. If the car carrying the tank is severely jolted or bumped, the liquid in the tank may be splashed upward con- I siderably, and these surgings would spoilthe accuracy of the readings on the indieating ammeter 7- if no shield or casing were provided around the buoyed member. However, with this casing 33 positioned asdescribed, liquid can onlypass through the the buoyed member subjected .to the ap 'the lowerF-portion' of the buoye after the-manner shown iuFigs. 1 and 2 can readily be figured out so as to compensateby a switchin lever )roximately true level of the liquid regardless of such splashing or surging of the main body of the liquid.

To facilitate the attaching of the device to an ordinary tank, I may employa lower clamping member 32 having a central raised portion 33 formed to tit-into the hole bored in the top -of the tank and slightly nar-' rower than the diameterof-this-lmle, so that it can be inserted through the latter. 1

also desirably provide some means for limltmg the downward 1no\-'en 1ent of the buoyed member in'-the'casing 33 during the assemblyof the parts, as for example by disposing the lower emlwof the buoyed member at a relatively short distance above the bot tom plate 37 of the surge-preventing casing While various materials may be employed for the buoyed member 3, the general action willialways be the same, since an y partially immersed objeetdisplaces its own weight of liquid,and I: have found jordinary wood turnings', satisfactory for this pur 'iose. Such. a wooden member may be given a coating of shellac or the like for keepin} the liquid from-penetrating the same, although the amount of liquid ed member accordingly, t

tank. Ihus' with a tank of a cylindrical vertical section, a downward. ta ring of for J'thejcurvature-of-thc bottom of the tank.

I am aware that electricallyindicating liquid gauges havewheretofore been .constructed with rheostats controlled stepwise geared or otherwise connected to a pat in the liquid. .Vithsuch arrangements, the indicator hand moves stepwise also and the disposing of a fioatin the main body of liquid subjects this float to the surging action which is quite marked when the gauge is used on a vehicle.- Hence the indicator needle in such gauges vibrates greatly when the vehicle is in use and may seriously mislead the usehtas to its indications. With my presented I struction, the variation -in resistance is cont ed, thus entirely avoiding anyjerky move- .ment. So also, the use of my guard easing or shield keeps the level of the liquid adjacent to the buoyed member so nearly conwhich would thus pen-1 etratc, an uncoated wooden member would be to member tank 4'1 such connections being easily made at the usual-petcoek openings, thereby permitting house a metalcup uon'sly gradstant as to avoid the undesirablevibrating of the Indicator hand. thereby making the indicator easily read and highly dependable eveirwll'en the vehicle on which my gauge is used Is traveling over rough ro'a(ls. So also,

I entirely avoid any danger of span-king such as may occur in rheostats having a' switch arm moving from contact to contact and hence eliminate thelire risk even when using mv gauge in connection with a gasoline tank.

However, while I have heretofore de-' I 'ta-iner is not subject to tilting or jarring.

In this case,-thc adjustable spring 21 abuts at its top against the head 19B of a hollow guide member which has a cylindrical portion 41 slidably fitting tho'borc 43 of thebuoyed member 3. The lower 1presser meniberl-t is freely spacedfrom tie bottom 16 of the bore of the buoyed .member, and a I v thrust.member 44 is interposed between this trivialin lpi'oportion t'o-the totalvol' rdinary-ltank to have amaterial f n he zindi'cator. reading. .lVhere a fairly uniform scalcjis desired on the indi-' cating ammeter,,I-desirablv shape the buoy-- 1c shaping being dependent on the: vertical section of the -es er member and a metal plug 45 socketed the'buoyed member. With this construc-' tron, the thrust member desirably extends- .stem {10 -which houses the resistance.

9 shows a simplified arrangement of a Fi typcfs'uitable for use with the lubricating oil tank's-ofvehicles 0r thelike. In this case, an auxilia teasing 46 isconnected to the oil y vertically spaced pipes 48 and 49,

.o'1 l t0. present the same level in the auxiliary 'ca'slng-fasin' themain tank. Floating in the oil within the casing 46 is a wooden block '50 which is hollowed out at its 11 per end to 51 connected by a flexible strip 52 to one. side of the circuit. A lower presser member 53' rests on .the bottom of the cup 5 1and supports the carbon pile 4, while an npperpresser member 54 is interposed between thetop of the carbon pile and the top of the casing 46 and electrically connected to the other side of the circuit.

I claim as my invention e v 1. .A. gaugefor liquid within a tank, in-. eluding at'member immersed to a varying slidable in the v means inte 'betweenthebuoyed meme.

- iligly s p q' 't extent in the liquid according to the depth A .of liquid in the tank and continuously buoyed by the liquid, means guiding .the

. taining the resistance under compression.

2. A gauge for indicating the height of liquidin a tank, comprising an upright cylindrical casingsupported within the tank and having upper and lower ortions communicating with'the interior the tank, the casing being somewhat shorter than the height of the tank. a buoyed member guided within the casing for. vertical movement and having clreular horizontal sections, a re-' sistance member arranged soas to be compressed by upward movement of the buoyed member, and means for indicating variations in the resistance of the resistance member;

the diameter of the-buoyed member varying downwardly from .the top to the bot-tom thereof in approximately joint proportion to the drop in voltage'through-the resistance according to the pressure onthe latter and to'the relative'horizontal sectional areas .of the tank at different heights of the latter substantially as describe 3. Ajgauge for liquid within a tank, in-

eluding hollow guide member depending within the tank, upper and lower pressure members withingthe guide member and a',

compressible resistance between them, the two presser members fitting the guide -mem her to substantially. seal the bore of the latter against the entrance of liquid, a buoyed member within the tank; and guid- .edby the guide member and extending below the latter, the upper resser member being fixed with respect to t e guide member and the lower presser member being vertically slidable in the guide member.

eluding hollow lgui e member depending 'within thetank, upper andlower presser members within the guide member and a compressible resistance between them, the

two presser members fitting the guide memher to substantially seal thebore of the latter d 'thinth tank (1 (led entrance of liquid,v a buoyed by the 'gui "member'and extendingzbelow A the latter, the upper "presser memberi fixed with respect to the guideim'ember an the .lower presser memberjbeing vertically 'de member,

ber andthe ower epresser member m the'guidemember.--

tween the v ,posed witim the latter, a compressible re- 4. A gauge forli uid within a tank, m-

andfspring.

resser member for yield 5. A gauge for liquid'within a tank,

the buoyed member for vertical movement, a compressible resistance operativcly interposed between the buoyed member and the tank so as'to be compressed according to the lifting of. the buoyed: member by theliquid, and a casing housing 1 the buoyed member, the casing-having an upper air m let and a lower liquid inlet, the casing beingformed to ailord a narrow space between it and major portion of the buoyed member so as to prevent a surging of liquid within the casing.

6. A liquid gauge, member, guide means for said buoyant memher, a compressible resistance element housed within said guide means, a resilient support interposed between the buoyant mem her and guide means, a compression member disposed between the buoyant member and resistance element, and means normally urgmg sald compression member away, from said resistance element whereby expansion of the latter is permitted. 4

7. liquid gauge, comprising abuoyant member having a recess therein, guide means for said buoyant member extending into said recess, a compressible resistance element housed within saldguide means, a resilient support interposed between the buoyant member and comprising a buoyant guide means and disposed w'ith- 'cluding a buoyed member, means guiding in said recess, means carried by said buoyant member and engaging the resistance member to compress the latter when the buoyant member is moved in one direction, and

meansnormally urging the compression member in an opposite direction to permit' expansion of the resistance element.

8. A liquid gauge formed to be disposed within a tank, comprising a float llavlng a recess therein, hollow guide means for the float having one end secured to said tank and its opposite end disposed within said recess, a resilient support interposed beguide means and float and, dis

sistanee e ement' within said .guide means, means carried by'said float for compressing said resistance element, and a liquid surge preventing easing formed to be secured to said tank and surrounding said float and uide means, said casing having a perforated ttom to admit liquid thereto for actuating the float and said compressible resistance to indicate the varying depths ofliquidinthe 9.- A-liquidgauge formed to be disposed within a tank, comprising a: buoyant member, guide means for said buoyant member,

a; compressible resistance element within saigefuide means, a resilient support interpo between the buoyant, member and guide means, a compression member disposed between the buoyant'member and resistance element to support the latter, and resilient means dispose between the guide means and compression member for normally urgin said compression member away from t e resistance element whereby expansion of the latter is rmitted.

10. In a liquid gauge or tanks or the like, compressing a float having a recess formed in its upper end, guide means for the float formed to be secured to said tank and havin one end disposed within said recess,

.a resi ient support interposed between the guide means and'float, a liquid surge preventin casing for the floatformed to be secured to said tank andhavin a series of openings in its bottom wall, and a guide pin carried by said float and movable through one of said openings. 7

. 11. A liquid gauge comprising a buoyant member having a recess therein, hollow guide means having a portion disposed within said recess, an ad ustable resilient support interposed between the guide means and buoyant member within said recess, a compressible resistance element within the guide means, a compression member having one end seated upon the bottom wall of the recess and its opposite end engaging and supporting the resistance element, and spring means normally urging said compression member away from said resistance element whereby expansion of the latter is permitted.

Signed at St. Louis, Missouri, May 15, 1925.

HARRY B. MARSHALL. 

